Larger imageThis unusual building with a tall story, long spans and large windows was severely damaged in the 1933 Long Beach Earthquake.

Source: Harold Engle, NISEE

The Problem

Buildings with irregular configurations, unusual designs, long spans, large assembly areas, or other unique features can be more vulnerable to earthquake damage than simple buildings. Numerous parking structures suffered partial collapse during the Northridge earthquake.

How to Identify

Consult with a qualified engineer or architect to identify the hazards, if any, of unusual designs and features. A building that is anything other than a plain box with four walls, floors, and a roof needs careful engineering attention. Irregularities in the building's footprint can be earthquake weaknesses.

Buildings with long spans over large assembly areas such as theaters, auditoriums, and churches should be carefully evaluated, since a collapse could be catastrophic.

Larger imageThis six story lift slab building collapsed in the 1964 Alaskan Earthquake.

Source: Karl Steinbrugge, NISEE

The Solution

The earthquake weaknesses of irregular or unusual building features can be reduced by strengthening or other means. You should rely on the advice of a qualified engineer or architect.